Method and apparatus for separating solids of different gravities



F. PARbEE Apf .30, 1940.

METHOD AND APPARATUS FOR SEPARATING SOLIDS OF DIFFERENT GRAVITIES Ill..-

6 Sheets-Sheet 1 INVENTOR Y 1"7WJ/VKP4/PDEE.

Filed Dec. 3, 1938 ATTORNEY.

A ril 30, 1940. F. PARDEE 2.199.091

METHOD AND APPARATUS FDR SEPARATING SOLIDS OF DIFFERENT GRAVITIES IFiled Dec. 5, 1938 e Sheets-Sheet 2 I INVENTOR. fk'mwrzeieozz F. PARDEEApril 30, 1940.

METHOD AND APPARATUS FOR SEPARATING SOLIDS 0F DIFFERENTGRAVITIES FiledDec. s, 1938 s sheets-sheet 3 fkA/YKBARDEE ATTORNEY April 30, 1940. I F,PARDE 2.199.091

METHOD AND APPARATUS FOR SEPARATING SOLIDS OF DIFFERENT GRAVITIES FiledDec. 3, 1938 6 Sheets-Sheet 4 INVENT OR.

EANKJQIRDEE.

ATTORNEY.

April 30, 1940. FQPARDEE 2.199.091

METHOD AND APPARATUS FOR SEPARATING SOLIDS OF DIFFERENT GRAVITIES FiledDec. 3, .1938 I 6 Sheets-Sheet 5 1N VENT OR.

BY ZRANKZ Bq/E'OEE.

April 30,1940. F, P R E 2.199.091

METHOD AND APPARATUS FOR SEPARATING SOLIDS OF DIFFERENT GRAVI TIES FiledDec. 3, 1938 6 Sheets-Sheet 6 I I-Z 85 INVENTOR. Z7194 xv/rfia RDEE'.

TTORNEY.

Patented Apr. 30, 1940 UNITED STATES PATENT OFFICE METHOD AND APPARATUSFOR SEPARAT- ING SOLIDS OF DIFFERENT GRAVITIES Frank Pardee, Hazleton,Pa., assignor to Anthracite Separator Company, Hazleton, Pa., acorporation of Pennsylvania Application December 3, 1938, Serial No.243,733

20 Claims. (Cl. 209-455) My invention relates to a method and apparatusIt will be understood that the rotation of the for separating a mixtureof solids of different scrapers over the conical surface is a relativedensities or specific gravities such, for example, movement and will beaccomplished equally Well as a mixture of coal and slate. if the conicalsurface is stationary and the scraper Coal as it is mined generallycontains slate or be rotatecL-or if the scraper be stationary and the 5other rock. Before the coal can be sold comsurface rotate or ifthescraper and conical plate mercially the slate must beremoved. Inremovrotate in opposite directions. ing the slate it is desirable toavoid, as much as The material to be separated or classified intopossible, any mechanical handling which would heavier material, such asslate, andlighter mate- )0 tend to break up the coal by attrition. Mypresrial, such as coal, is supplied at an intermediate ent inventionprovides a method and apparatus point on the slope so that any slatecarried over whereby the coal may be buoyed and lifted above with thecoal passing to the lowermost edge will the slate and separatedtherefrom with a minibe caught and retained by the scrapers below themum of movement and of attrition with the slate. supply point and movedupwardly. Any coal In my invention a mixture of coal and slate, carriedabove the point of supply will have an of approximately the sameparticle size, is fed opportunity to be buoyed over the scraper bladesin successive quantities or continuously, to an and carried downwardly.-inclined plate preferably a conical plate or in- The material ispreferably distributed uniformverted conical plate, having a dischargeopening ly throughout a narrow ring-like zone between so or edgecentrally of the plate and a peripheral the upper and lower edges. Inthe case of a discharge edge. Shallow scrapers move over the conicalseparating surface, this zone is of annular inclined surface in such away as to slide or push form concentric with and between the inner andthe material upwardly or against the slope of outer discharge edges.

the surface. At the same time a fluid, such as In apreferred form of theinvention, the mate- .1 water or other buoyant fluid, or a fluid mixturerial is distributed on an annular plate by a spout comprising liquids,solids, gases, or combinations that travels circularly over the annularsurface ofthem, is circulated upwardly through openings and a spiralscraping blade which pushes the distributed over the surface of theplate and material uniformly over the edge of the annular exerts agreater lifting effect on the pieces of plate. The annular plate maybestationary and m) coal which are lighter than the pieces of slate thescraper blade and distributing spout rotate, 3

or rock and buoys them over the upper edge of or the blade and spout maybe stationary and the the scraper and thence toward the lower edge ofplate rotate. The mixture of slate and coal, or .the cone. othermaterial to be separated, may, however, be

As the slate is moved progressively upwardly distributed by any othersuitable distributing 5 on the inclined surface, it builds up to athickness means.

approximately equal o the height of the moving The various features ofthe invention are illusscrapers, and because of the incline of the platetrated by way of example in the accompanying and the buoyant action ofthe fluid flowing updrawings in whichwardly therethrough and downwardlythereover, Fig. 1 is a vertical section of a separating appathe coal iscarried over the scrapers to the lower ratus embodying a preferred formof the inven- 40 edge of the inclined pla In this y the Slate tion..Fig. 2 is a plan view of the apparatus shown passes v t upper edge andthe we! Over the 'in Fig. 1. Fig. 3 is a horizontal section taken onlower discharge e of the plate the line 3+3 of'Fig. 1. Fig. 4 is avertical section When the conical surface is such that the outer I of ah of the apparatus of Fig 1 taken on a higher than. lower centraldlscharge larger scale. Fig. 5 is a plan view of a separator p thescrape W111 act to push the mate showing a modified distributing meansfor disrial toward the outer edge, but when the surface t ributing thematerial in a circular or annular slopes upwardly toward the inner edge,the scrapzone on theseparating plate. Fig. 6 1s a vertical ers will tendto carry the material toward the th n th t f 5 F1 ,upperinner edge. Thescrapers maybe of any Ion 8 us 0 suitable type. However, the spiralscraper or 15 a of feefimg of the series of concentric spiral scrapersrotated conembodlment Shown m F 8 a plan tinuously serves effectively tomove the material view and Fig. 9 a -vertical section of a modifiedradially inwardly or outwardly according to the form of feeding device.Fig. 10 is a plan view gs arrangement of spirals and direction ofrotation. .and Fig. 11 is a view of a still further modification.

vided with a suitable packing, and is provided at spaced intervalslwithopenings 49 closed by upwardly opening valve plates-50.

I Consequently, as the plate 41 moves upwardly the valves 50 close andforce the fluid contained above the plate upwardly through the openings-40 in the plate .30, the inner edge of the piston plate 41 forming asufficiently fluid-tight closure on the central well 3|. The fluid thusforced upwardly on the plate 30 overflows the lower edge,thence'downwardly through the openings in the bottom plate 42 and entersthrough openings 5| and past the inwardly opening flap valve 52 tore-enter the space below the plate 41, as indicated by the arrows inFig. 1. As the plate 41 descends the fluid trapped below it flowsupwardly through the openings 49 lifting the valves 50, the valves 52being closed by the back pressure.

Any suitable means may be employed for reciprocating the piston plate41. Forexample, the plate may be supported at suitably spaced interv2.15by rods 53 secured at their upper ends to the plate 41 and extendingthrough packing boxes 54 in the bottom wall 48 and thence to aconnection with a driving head or spider 55. The latter in turn may bereciprocated by means of a rocking lever or walking beam 56 fulcrumed ina hanger 51 from the lower side of the bottom 48 and connected by meansof a forked head 58 to a guide stem 59 mounted on the spider 55. Theguide stem 59 may be guided in a guide 60 supported centrally at thesupport leg 6! for the tank structure of the separator. The outer end ofthe walking beam 56 may be reciprocated by any suitable '"motive means,indicated at 62 in Fig. 3.

Through the above apparatus, the coal or other material to be separatedis delivered in a substantially annular feed between the inner and outerperipheries of an inclined or conically curved plate which is perforatedor otherwise permeable to fluid. The lower part of the depositedmaterialis to a discharge edge for the heavier material, such as slate, whilethe entire mass is buoyed up at intervals so as to cause the lightermaterial, such as coal, to rise to the top and roll or flow downwardlywith the buoying liquid toward the lower edge. I a

In the example shown in Figs. 1 to 9, the surface 30 slopes upwardlytowards the center so that the lighter material discharges from theouter periphery and the heavier material from the inner periphery. Thisrelationship may, however, be inverted and the coal discharged centrallyand the slate, or heavier'material, peripherally, where such anarrangement is more adas amixture of coal and slate is delivered from adelivery spout 66 of the hopper 61 angularly on to a rotating conicaldistributing plate 68, the rate of feed being controlled by anadjustable control collar 69 about thelower part of the deliverychute66. The direction of rotation for the spiral shown in Fig. 10 would becounter- .clockwise and thus tend to carry the slate upwardly toward theperiphery where it overflows into an annular channel. 69', while thesurging gradually dragged, upwardly lto 9 may be employed with theseparating arrangements shown in Figs. 10 and -11. Y in themodifiedar-rangement hown in Figs. 12 and 13, the feed hopper-1l isarranged at the side of a plate 12, similar to the separating plate ofFig. 1, and provided with a number of spiral scrapers 13 carried androtated by radial arms 14 extending froma central shaft 15. A quantityof material to be separated, regulated by a gate 16, flows 'sidewise outof the hopper 1| on to the plate 12 and is distributed and carriedinwardly by the rotating spiral scrapers 13, thereafter the separationof the coal and slate takes place in the same manner as in the apparatusshown in Figs. 1 to 9 inclusive. Separate scrapers 11 are provided inthe coal receiving channel 18 to carry the coal therein to a dischargechute and elevator 19. I

The sizes of the openings 40 in the plate'30 will be regulated to giveany desired speed to the jets issuing from these openings and thus tocontrol the buoyant effect of the fluid. If desired, the density of thefluid may be increased by dissolved or suspended material to increaseits buoy ant effect, although this is not necessary and any fluidavailable may be employed.

It will be understood 'alsothat the fluid may be introduced in thespecific manner shown above, or in any other suitable manner whereby itis introduced between the turns of the spiral and exerts a buoyanteffect on the material to be separated. Preferably the current of fluidis given a pulsating or surging effect as this is most effective incausing a separation, but the supply of fluid between the spirals may becontinuous.

It will be obvious that the scrapers may be of any suitable shape andmounted in any suitable manner and that any relative movement of scraperand supporting surface may be employed that will serve to push thematerial upwardly on the surface.

The apparatus as described in the accompanying drawings illustrates theflexibility of the apparatus and its adaptation for various conditions.In the apparatus, the coaland slate respectively pass in short directpaths in opposite ,directions to the opposite edges of the annularseparating plate. The coal, as it is being buoyed by fluid,'is carriedwithout attrition and breakage. The apparatus is simple in operation andone with a minimum of wearing parts.

Various modifications in detailmay be made by those skilled in the artwithoutdeparting from the invention as defined in the following claims.

What I claim is:

1. Apparatus of the type described which comprises a material supportingplate permeable to fluid and having a central discharge opening and aperipheral discharge edge, and being inclined radially between saidopening and said edge, spirally arranged scrapers of small verticaldimensions to form a substantially continuous barrier to the downwardmovementof solids onsaid plate and movable on said plate, means torotate said scrapers about a central axis to move material toward theupper part of said plate. and means to circulate a buoying fluid throughsaid plate to buoy the lighter material over said scrapers' tothe lowerdischarge end of said plate and M heavier material is moved by saidscraper to the upper edge of said plate and means for causing apulsation in the fluid suppliedto said spiral path.

15. Apparatus of the type described which comprises a conical perforateplate having a central discharge opening and a peripheral dischargeedge, spirally extending scraper of small vertical dimension and forminga substantially continuous barrier between said edge and said opening,means to supply material to be separated to said plate, a chamber belowsaid plate, and a plunger in said chamber to force liquid upwardlythrough said plate to overflow downwardly over said plate and return tosaid chamber the level of liquid on said plate being below the upperedge of said plate, and means to rotate said scraper in a direction topush material upwardly over said plate and permit the liquid to buoy andcarry the uppermosttof said material over said scrapers to and over thelower edge of said plate.

16. Apparatus of the type described which comprises a conical perforateplate having a central discharge opening and a peripheral dischargeedge, spirally extending scraper of small vertical dimension and forminga substantially continuous barrier between said edge and said opening,means to supply and distribute material in an annular zone to saidplate, a chamber below said plate, and a plunger in said chamber toforce a liquid upwardly through said plate to overflow downwardlythereover and return to said chamber the level of liquid on said platebeing below the upper edge of said plate, and means to rotate saidscraper in a direction to push material upwardly over said plate and permit the liquid tobuoy and carry the uppermost of said material over saidscrapers to and over the lower edge of said plate.

17. Apparatus of the type described which comprises a plate having aninclined surface, a scraper of low vertical dimension moving over saidsurface to push material up the slope of said surface, means tocirculate a buoyant fluid intermittently upwardly through said plate tobuoy the lighter particles over the upper edge of said scraper anddownwardly on the slope of said plate, and means to supply material tobe sepseparated to the inclined Surface of said plate.

19. Apparatus of the type described which comprises a frusto-conicalperforate plate having a central discharge opening, a peripheraldischarge edge, means to separate a mixture of heavier and lightermaterials and to convey one of said materials to said central dischargeopen ing and the other of said materials to said peripheral dischargeedge and means to supply material to be separated to said frusto-conicalplate, said means comprising a plate above said frustoconical plate andhaving a circular discharge edge, means to sup-ply a mixture of materialto be separated to said uppersupply plate and means to push said mixtureuniformly and progressively over said discharge edge and onto saidfrusto-conical plate in a zone between said peripheral edge and saidcentral opening.

- 20. The apparatus of claim 19 in which said means for supplyingmaterial to and discharging material from said supply plate comprising arotating chute and a spiral scraper rotatable above said plate to pushmaterial over said peripheral edge.

- FRANK PARDEE.

